| 摘要 |
PURPOSE:To heat a coil to a high temperature by a small temperature deviation, by providing a space of specified height between a furnace floor surface and a coil base plate, providing a part of burners within a range of height of this space, and heating a coil in a retort. CONSTITUTION:On the lower part and the middle part of a furnace body 1, a burner 2 is provided in the tangential direction of a retort 8. The retort 8 is fitted into a furnace floor 3 by a seal groove 13, and in the retort, pillar-like support fittings 10 are provided on the lower part in the center of a coil base plate 5 on which a coil 6 has been placed, and a space 11 of >=300mm. in the direction of height is formed between the surface of the furnace floor 3 and the coil base plate 5, so that the lower burner 2 is positioned within a range of height of the space 11. In this state, when the coil 6 is heated through the retort 8 by the burner 2, radiation heat 12 from the lower side furnace of the retort 8 heats the coil 6 from downward, a temperature deviation in the coil 6 is reduced, and it is possible to heat the coil 6 to a high temperature of >=1,000 deg.C. |
